1. Field of the Invention
This invention relates generally to breathing ventilators, and more particularly concerns a ventilator airway fluid collection system including a fluid collector vial that is connected to an airway of the ventilator, and which allows PEEP to be maintained in a patient breathing circuit when the fluid collector vial is removed for emptying.
2. Description of Related Art
Breathing ventilator systems conventionally provide a breathing gas at elevated pressure levels. Pressure support is also known in the art by other names, e.g. inspiratory assist, pressure assist, or inspiratory pressure assist. Pressure in a ventilator airway is commonly maintained at PEEP (Patient End Expiratory Pressure, a baseline pressure value) to assist patient breathing efforts. Breathing gas is also often supplemented with a higher proportion of oxygen than is found in the ambient atmosphere, and is commonly humidified. Consequently, moisture regularly condenses in a ventilator airway, and one or more fluid collector vials can be placed in strategic locations in the airway to collect such fluid condensate.
A common problem with such fluid collection systems is that PEEP can be lost to the patient when the airway is opened to atmospheric pressure when such collector vials are removed to dispose of collected fluid. Fluid can also be sprayed out of the airway if the ventilator is operating when the fluid collection vial is removed, which can be unpleasant and unhygienic.
One known solution to this problem has been to provide spring loaded seals which close off the fluid collection opening in the airway when a collection vial is removed. However, such spring loaded seals can be expensive, difficult to clean, and can fail due to blockage of the seal, cracking of the seal, failure of the spring, and similar problems.
It is therefore desirable to provide a ventilator airway fluid collection system that is less complex and less expensive, more robust and reliable than such spring loaded seal systems, that will allow PEEP to be maintained in a patient breathing circuit when a fluid collector vial is removed for emptying. It would also be desirable to provide such a ventilator airway fluid collection system that can readily be substituted for existing fluid collection systems. The present invention meets these needs.